1. Field of the Invention
The present invention relates to an appearance processing method, and more particularly, to an appearance processing method capable of precisely processing a minute spherical surface or an aspheric shape and performing a large quantity of fabrication with a uniform processing precision and an aspheric lens fabricating method using the same.
2. Description of the Conventional Art
Recently, as multimedia and an information communication technique are fast developed, an optical data storage, a fiber-optic system communication system, a display, and etc. are miniaturized. As an optical system is miniaturized, individual optical components have to be miniaturized and especially lenslets corresponding to a core factor of an optical system have to be miniaturized. The reason is because a processing precision has to be maintained as a miniaturization ratio in order to maintain an optical function of an existing lens and reduce a size of a lens itself.
An ultra-micro refractive lens can be variously applied as a collimating lens, an objective lens, a solid immersion lens, and etc. as shown in an example of a pick-up optical system of a micro optical data storage which can be applied to a portable information device and etc., and a surface of the ultra-micro refractive lens has to be processed not only as a spherical shape but also as an aspheric shape.
According to the conventional lens processing technique, a spherical lens or an aspheric lens of a desired shape were implemented by using a minute polishing method or various forming methods such as a precise molding, pressing, and an injection. The conventional technique is proper to fabricate comparatively voluminous refractive lens, but it is difficult to uniformly process a micro-lens of which diameter is smaller than a millimeter according to the conventional technique.
In addition to said lens fabricating technique using a mechanical polishing method and forming methods, there is a reflow technique for processing a partial spherical lens having an arbitrary radius of curvature by a generated surface tension by heating optically transparent polymer material with a temperature more than a glass transition temperature, and there is a method for fabricating lens by transferring a curved surface shape formed by the reflow technique on a predetermined substrate by using a reactive ion etching technique or an ion milling technique.
By said conventional micro-lens fabricating methods, a spherical lens can be miniaturized. However, it is limited to minutely process a micro-lens of which a spherical aberration is removed and a processing uniformity is lowered thus to degrade a mass production.